Jean D Amour Kubwimana: Implement Data Structures and Algorithms Solutions

[Jdamour12]

This pull request includes solutions for three data structures and algorithm challenges:

1. Reverse a String Using a Stack:

   • Implemented a stack-based approach to reverse a string.
   • Function: reverse_string(s: str) -> str
   • Example: reverse_string("hello") returns "olleh"

2. Queue Implementation Using Two Stacks:

   • Developed a queue class using two stacks for enqueue and dequeue operations.
   • Class: QueueWithStacks
   • Methods:
     • enqueue(x: int): Adds an element to the queue.
     • dequeue() -> int: Removes and returns the front element of the queue.
   • Example:

     q = QueueWithStacks()
     q.enqueue(1)
     q.enqueue(2)
     print(q.dequeue())  # Output: 1
     print(q.dequeue())  # Output: 2

3. Find the Maximum Element in a Linked List:

   • Implemented a singly linked list with a method to find the maximum element.
   • Class: LinkedList
   • Method: find_max() -> int
   • Example:

     ll = LinkedList()
     ll.append(3)
     ll.append(1)
     ll.append(4)
     ll.append(2)
     print(ll.find_max())  # Output: 4

The implementations include user input prompts and descriptive output messages. The code is well-documented and adheres to best practices for clarity and efficiency.